高频电磁辐射危害屏蔽防护措施效果评价

高频电磁辐射危害屏蔽防护措施效果评价淄博市卫生防疫站（２５５０２６）孙志杰，苗泉，蒋绪亮，张倩我市工业高频生产主要分为介质加热（高频塑料热合）和感应加热（以高频淬火和高频焊管为主）两大类。由于多数厂家原有设备缺乏屏蔽防护措施，致使高频电磁波泄漏严重，...     

射频设备电磁辐射的危害及防治措施

科学家们称电磁波为"幽灵电波",不仅仅因为它看不见、闻不到、摸不着,更主要是它危害范围广而且日趋严重。     

大功率高频感应加热淬火场所电磁辐射分布及防护研究

目的 检测了解大功率高频感应加热淬火场所的电磁场分布,以研究电磁辐射对操作人员的影响。方法 按国家标准规定的测试方法。结果 经对30 kW、60 kW、100 kW等71台机器的电磁场强度测试,在工作人员操作位,95%的测量点电场强度、100%的测点磁场强度超过国家标准限值。结论 必须加强操作人员电磁辐射防护。     

高频热合机（直刀型）防护效果评价

高频热合机对人体健康的危害及其对环境的污染问题在80年代进一步得到了有关部门的注意和重视。目前在我国高频热合机尚无较完善的防护措施,因而相当部分强电磁辐射问题仍未得到解决。天津研制的高频热合机“屏蔽防护技术”,经有、     

对高频电磁辐射防护的探讨

<正> 交流电的频率达20万HZ以上时,交流电路的周围便形成高频电磁场。高频电磁场为有源非电离辐射,其特点为电、磁场交替作用,互相转移而形成高频电磁波,向空间传播(辐射),具有波的反射与折射等性质。由于科学技术的发展,高频电磁场已广泛用于广播、通讯、工业、国防、气象、医学科研等领域。其对人体的危害及环保污染问题更加受到人们的重视。本文通过对某高频焊管厂高频电磁辐射防护前后的调查测试,岗位工人健康体检的统计分析,探讨了高频电磁场辐射对岗位工人的危害及防护。     

高频焊管机电磁辅射防护治理的研究

对高频焊管机电磁辐射防护治理研究的过程也是对原设备进行结构改造、布局调整和匹配调试的过程。是反复探索、逐步完善成功的。该机改造后经过近两年的生产运行,设备运转良好,电磁辅射治理效果稳定可靠,未发现任何异常问题。实践证明,该治理方案效果明显,投资少、见效快,社会和经济效益显著,具有广阔的推广和应用前景。     

电磁辐射的危害及防护

随着现代科技的高速发展,电磁辐射对人体的危害越来越严重,被人们称为"隐形杀手".介绍了常见的电磁辐射源,分析了电磁辐射危害人体的机理及对人体产生的危害,并提出了防护电磁辐射的相关措施.     

制鞋工人高频电磁辐射暴露的测量与评价

目的 了解职业人群高频电磁辐射职业暴露现况.方法 以2家制鞋企业高频热合生产车间作业岗位为调查对象,分别对其电场强度进行调查分析.结果 2家厂53个作业岗位,90.6%的岗位电场强度超过国家标准25 V/m的要求,加屏蔽防护板的高频热合作业岗位仅有1个测点高于标准值1.20 V/m,超标率明显低于未加屏蔽防护板组.结论 高频热合作业工人存在较强的高频电场暴露,应采取屏蔽等综合措施控制其职业危害.     

某医院一台核磁共振成像系统电磁辐射防护调查评价

核磁共振成像系统(MRI)以其软组织分辨率高、多层面成像、无电离辐射损伤等优点广泛应用于临床。MRI装置可产生极低频磁场和高频电磁场^[1],特别是极低频磁场较大,国际肿瘤研究机构(IARC)已将极低频磁场确定为人类可疑致瘤原。     

屏蔽措施对电磁辐射致学习记忆障碍的防护

目的 探讨电磁辐射对大鼠学习记忆的影响及其机制，观察铝箔的不同屏蔽方式对电磁辐射的防护效果。方法 采用主动回避反应(AAR)和一次性被动回避反应(PAR)观察电磁辐射后大鼠学习记忆能力，采用Fura-2荧光检测海马突触体游离钙的变化，以及采用铝箔进行全身屏蔽和躯干屏蔽后对学习记忆能力和海马突触体钙含量的影响。结果 电磁波辐照可引起大鼠长时记忆和短时记忆能力减退，辐照后即刻和24h海马突触体游离钙呈双峰状升高，全身屏蔽后电磁波辐照对大鼠学习记亿能力和海马突触体游离钙基本不产生影响，躯干屏蔽对以上指标白乞变化影响不明显。结论 电磁辐射可明显影响大鼠学习记亿能力和海马突触体游离钙含量，海马突触体游离钙超载可能是大鼠学习记忆障碍的直接原因。全身屏蔽方式对电磁辐射具有较好的防护效果，而躯干屏蔽对电磁辐射基本无防护作用。     

高频淬火设备电磁场防护措施的设计与效果评价

高频淬火的主要职业危害因素是高频电磁场。该文对某高频设备产生的高频电磁场分两期进行了屏蔽和接地防护措施。在加强操作位的屏蔽和加强接地的二期防护措施后，电场强度有较大幅度的下降，均未超过87V/m国家标准，从而控制了高频电磁场的职业危害，保护了作业人员的身体健康。     

医学装备的电磁辐射及其生物效应的探讨

将对各类医学装备的电磁辐射可能给医务人员及患者带来的身体损害进行定性分析,结合相关实验数据的分析,探讨与医学装备相关的各类电磁辐射可能产生的生物效应,并初步研究对应的防护措施,使医学装备在发挥其重要的临床救治作用的同时尽量减低电磁辐射对使用人员身体健康所产生的潜在危害。     

Gender-specific reproductive outcome and exposure to high-frequency electromagnetic radiation among physiotherapists

The aim of this case-referent study was to investigate reproductive hazards other than congenital malformations after exposure to high-frequency electromagnetic radiation. Cases and referents were sampled from a cohort of pregnancies of members of the Union of Danish Physiotherapists through linkage of the union file with national medical registers. Case groups were spontaneous abortions and children with low birth-weight prematurity, and stillbirth/death within one year. Exposure to high-frequency electromagnetic radiation before and during pregnancy was assessed through telephone interviews. As referents to the 270 cases, 316 pregnancies were randomly sampled. A total of 8.4% did not participate. Only 23.5% of the children born by the highly exposed mothers were boys. This value is a statistically significantly altered gender ratio showing a dose-response pattern. High-frequency electromagnetic radiation was furthermore associated with low birthweight, but only for male newborns. The other outcomes were not statistically significantly associated with exposure to high-frequency electromagnetic radiation.     

Congenital malformations and exposure to high-frequency electromagnetic radiation among Danish physiotherapists

A cluster initiated the present case-referent study to assess the relation between exposure to high-frequency electromagnetic radiation and congenital malformations. Through the linkage of a cohort formed from a union file of Danish physiotherapists with complete national registers of pregnancy outcome, cases (pregnancies terminated by the birth of a malformed child) and referents were identified. From responses in a blinded telephone interview without knowledge of case status, exposure to high-frequency electromagnetic radiation in the first month of pregnancy was assessed. Indices reflecting duration of exposure ("time") and maximum level of exposure ("peak") were composed. After a 7% dropout 54 cases and 247 referents were interviewed. No statistically significant associations between pregnancy outcome and high-frequency electromagnetic radiation were found (odds ratio 1.7, 95% confidence interval 0.6-4.3).     

电磁辐射对血脑屏障通透性的影响及其机制研究进展

血脑屏障(blood-brain-banjer,BBB)是存在于血液与脑组织之间的屏障结构,由脑微血管内皮细胞、基膜和星形胶质细胞足突组成.脑的毛细血管属连续型,毛细血管内皮细胞之间以紧密连接(tight junction,TJ)封闭,内皮外有基膜、周细胞以及星形胶质细胞突起的足突围绕.与机体其他部位的微血管相比,BBB的通透性极低,其目的是防止血液中的有害物质通过BBB而对神经元造成损伤,维持大脑微环境的相对稳定.     

Exposure modeling of high-frequency electromagnetic fields

We developed a geospatial model that calculates ambient high-frequency electromagnetic field (HF-EMF) strengths of stationary transmission installations such as mobile phone base stations and broadcast transmitters with high spatial resolution in the order of 1 m. The model considers the location and transmission patterns of the transmitters, the three-dimensional topography, and shielding effects by buildings. The aim of the present study was to assess the suitability of the model for exposure monitoring and for epidemiological research. We modeled time-averaged HF-EMF strengths for an urban area in the city of Basel as well as for a rural area (Bubendorf). To compare modeling with measurements, we selected 20 outdoor measurement sites in Basel and 18 sites in Bubendorf. We calculated Pearson's correlation coefficients between modeling and measurements. Chance-corrected agreement was evaluated by weighted Cohen's kappa statistics for three exposure categories. Correlation between measurements and modeling of the total HF-EMF strength was 0.67 (95% confidence interval (CI): 0.33-0.86) in the city of Basel and 0.77 (95% CI: 0.46-0.91) in the rural area. In both regions, kappa coefficients between measurements and modeling were 0.63 and 0.77 for the total HF-EMF strengths and for all mobile phone frequency bands. First evaluation of our geospatial model yielded substantial agreement between modeling and measurements. However, before the model can be applied for future epidemiologic research, additional validation studies focusing on indoor values are needed to improve model validity.     

Occupational and residential 60-Hz electromagnetic fields and high-frequency electric transients: exposure assessment using a new dosimeter

One problem that has limited past epidemiologic studies of cancer and exposure to extremely low-frequency (0-100 Hz) electric and magnetic fields has been the lack of adequate methods for assessing personal exposure to these fields. A new 60-Hz electromagnetic field dosimeter was tested to assess occupational and residential exposures of a group of electrical utility workers and a comparison background group over a 7-day period. Comparing work periods only, utility workers' exposures were significantly higher than background levels by a factor of about 10 for electric (E) and magnetic (B) fields and by a factor of 171 for high-frequency transient electric (HFTE) fields. When overall weekly time-weighted averages combining work and nonwork exposures were compared, ratios of the exposed to background groups were lower. B and HFTE exposure ratios remained statistically significant, with values of 3.5 and 58, respectively, whereas the electric field exposure ratio was no longer significant, with a value of 1.7. E-field exposures of the background group were the highest during the nonwork period, probably reflecting the use of electrical appliances at home. Residential E- and B-field exposures were in the same range as published results from other surveys, whereas occupational E-field exposures tended to be lower than exposures reported in other studies. The high variability associated with occupational exposures probably accounts for the latter discrepancy. Worker acceptance of wearing the dosimeter was good: 95% of participants found it to be of little or no inconvenience while at work. At home, 37% found the device to be inconvenient in its present form but would not object to wearing a slightly smaller and lighter dosimeter.     

亚慢性暴露高频电磁场对雌性大鼠性腺的毒性作用

目的 研究亚慢性暴露高频电磁场(HF-EMF,30 MHz)对雌性大鼠性腺的毒性作用.方法 选用清洁级Wistar雌性大鼠60只,按体重随机分为5组,暴露剂量分别为0、25、100、400、1600V/m,大鼠伞身暴露于HF-EMF,8 h/d,每周连续5 d,停2 d,共暴露56 d.辐射期间大鼠每3天称1次体重,第48天开始观察大鼠动情周期的变化,56 d后待大鼠处于动情期时取血清和卵巢,采用放射免疫法测定相火激素,HE染色法计算卵巢各级卵泡的数目构成比,用电子显微镜观察细胞超微结构.结果 各剂量组大鼠体重与卵巢湿重及脏器系数的差异无统计学意义(P0.05);100、400、1600V/m组大鼠动情前期时间分别为(15.00±5.06)、(11.40±2.05)、(10.56±0.96)h,明显短于对照组[(18.70±2.96)h],差异有统计学意义(P<0.01);400、1600 V/m组大鼠动情问期时间分别为(101.20±17.81)、(115.33±19.28)h,明显长于对照组[(69.80±11.42)h],差异有统计学意义(P<0.01).400、1600V/m组的黄体生成素(LH)水平[分别为(11.02±1.11)、(14.70±1.94)mU/ml]明显高于对照组[(8.70±0.53)mU/ml],差异有统计学意义(P<0.01);而雌激素(E2)水平[分别为(57.16±31.56)、(50.57±25.16)pg.ml]明显低于对照组[(95.04±32.62)pg/ml],差异有统计学意义(P<0.01);400、1600V/m组黄体数目构成比(分别为19.75%、19.04%)明显高于对照组(14.01%),差异有统计学意义(P<0.01),100、400、1600V/m组闭锁卵泡数目构成比分别为8.45%、9.95%、11.70%,明显高于对照组(7.72%),差异有统计学意义(P<0.01);而400、1600 V/m组成熟卵泡数目构成比(分别为1.50%、1.55%)明显低于对照组(3.36%),差异有统汁学意义(P<0.01);400、1600 V/m组仞/次级卵泡数目构成比分别为22.24%、21.09%,明显低于对照组(26.60%),差异有统计学意义(P<0.01).随辐射剂量的增大,细胞超微结构改变越明显,细胞核染色质成块,核仁边集,甚至出现核同缩、凋亡小体,线粒体出现肿胀、水肿,甚至呈空泡状.结论 HF-EMF(30 MHz、100～1600 V/m)对雌性性腺有毒性作用,其毒性作用表现在卵巢损害出现较早(如激素分泌功能改变).